Thermionic device



Dec. 22, 1925. 1,566,293

H. J. VAN DER BML THERMIONIC DEVICE Filed Sept. 4. 1919 Patented Dec. 22, 1925.

l 1,566,293 UNITED STATES PATENT OFFICE.

HENDRIK J. VAI nl! BLU.,- Ol' NEW YORK, N. Y., ASSIGNOR T0 WESTERN ELECTRIC OOIPANY, INOORPORATED, Ol' NEW YORK, N. Y., A CORPORATION OF NEW YORK.

THERHIONIC DEVIOE.

Application led September 4, 1819. Serial No. 821,653.

To nfl uliom 4il? may] concern.'

Be it known that I. HENDRIK J. vAN van BIJI.. a subject of the King of Great Britain, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in 'lhermionic Devices, of which the following is a. full, clear, concise, and exact description.

This invention relates to thermionic devices and a method for making the same, and concerns particularly the manufacture of audions.

An object of the invention is toavoid the necessity of sealing-in a flare to a main bulb structure, as has heretofore been the custom.

Another objectis to provide an improved simple mounting whereby the electrodes may be rigidly assembled prior to insertion in the bulb or tube, and may then be readily anl, in a simple manner, placed within the tu e. i

The invention in general comprises mounting and assembling the electrode structure, prior to its assembly within the tube, on a framework comprising a pluralityof rigid wires, which ha\'e been previously definitely spaced. The rigid space relation of these wires, from which the electrodes are supported, is maintained by connecting them through the intermediary of an insulating and supporting connection such as a bead of glass. f

After the electrode unit'has been thus assembled. the invention further comprises merely that this assembly be inserted into a glass tube, and, while held in the proper position within the tube, the open end of Vthe tube itself is heated and is flattened out over the extension of the lead-in wires, thus sealing the unit within the bulb or tube Withs out the usual re-entrant stem.

In the previous practice it has been found necessary to provide a flare on which a suitable stem or squash was formed, through which the lead-in Wires were passed. The quantity production of these flares and squashes generally yrequired expensive machinery. After the electrode unit was mounted on this stem or flare portion further expensive machinery has hereto been required to successfully seal-in the flare portion or stem unit to the main bulb structure.

As described above it will be noted that the equivalent or substitute for the usual stem portion is now formed from the lower end of the tube itself, and that the means.

for mounting the electrodes in a definite spaced manner is provided in the glass bead above mentioned which preferably fitsv snugly within the bulb but is not integral therewith. In this manner several expensive operations in the previous manufacture of tubes are eliminated.

The invention is illustrated in the drawlng in which Fig. 1 is a perspective view of a tube made in accordance with the invention; Fig. 2 is an elevation of part of the tube showing another arrangement wherein the insulating material is of a length substantially equal to the inner bore of the tube. As illustrated in the drawing (Fig. 1) the invention comprises an evacuated vessel 1, which may bein the form of a bulb or in the form of a tube as shown. This vessel has its lower portion or stem 2 collapsed around a plurality of lead-in Wires 3, 4, 5 and 6. These lead-in wires connect respectively to a plurality of rigid wires 7, 8, 9 and 10, which are formed as a frame member by being connected by a glass bead 11 or other insulating material which may be formed across these Wires in any suitable or Well-known manner. This insulation and supporting material may be of any desired length;` for instance, in Fig. 1 it is of a length shorter than the bore of the tube but, as shown in Fig. 2, it may be of a length to lit snugly Within the bore of the tube and thus serve as an additional means for maintaining the electrode unit rigid within the evacuated vessel. The rigid wire 10 extends above the glass bead 11 and is Welded along its length to a cylindrical electrode' 12, which in this case is an anode` The rigid Wire 9 extends above the glass bead 11 and is connected to the lower end of a spiral electrode 13, which in this case is a control electrode or grid. The rigid Wire 7 extends above the glass bead 11 and, by means of a resilient. spring member 14, is connected to the upper end of a filamentarv electrode 15, which in this case is the cathode, the lower end of which cathode is connected to the upper end of rigid Wire 8 above the glass bead. The spring member 14 provides means whereby the cathode may be maintained under a definite tension. The cathode is arranged substantially along the central axis of the tube and the other electrodes are arranged concentricallv around it. In the manufacture of this tube, the rigid wires 7, 8, 9 and 10 are held in a suitableing member secured to said conductors frame member outside the tube, while the glass bead is being fused across them.` After this is done the electrodes lare mounted thereon, the glass connection serving to maintain the proper space relation between the electrodes, in lieu of the usual stem l which is usually formed on the upper end of a flare portion.

l When this assembly has been completed,

the lead-in wires 3, 4, 5 and 6 are connected respectively to the lower ends of the rigid wires 7, 8,' 9 and l0, and this assembly is then inserted within the tube. Thelower end of the tube is then heated anda pair of pincers, or other suitable means, is used to Hatten the lower end of the tube itself 'over the lead-in wires and thereby seal the aS- sembly within the tube in a much simpler manner than has hereto been the case.

What-is claimed is:

1. An electron discharge device comprising a glass tube having one end collapsed to form an outwardly projecting tlareless stem, a plurality of conductors sealed in said stem and a plurality of electrodes each supported by one of said conductors. y

2. An electron discharge device comprising a glass tube having a portion collapsed to form an outwardly projecting liareless stem, a plurality of conductors Isealed in said stem, a pluralit of electrodes each supported by one of said conductors and an in sulating member secured to said electrodes whereby the space relation between the electrodes may be establishedbefore their insertion within the tube. l

3.' In combination, a plurality of conductors, a plurality of electrodes each supported by oneof said conductors and an enclosing vessel comprising a glass tube having one end collapsed about said conductors to form .an outwardl projecting areless stem.

4. In com ination, a plurality of conductors, a plurality of electrodes each supportel by one of said conductors, an insulatwhereb the space relation between said electro es is established, and an `enclosing vessel comprising a glass tube having one end collapsed about said conductors to form an outwardly rejecting iiareless stem.

5'. The combination of frame support members positioned parallel with respect to each other, electrodeA support'members po-i sitioned parallel to and between said frame members, means for uniting said members to form an electrode unit, an electrode extended between aligned support members, an electrode supported by one of said franw members, and means for supporting said unit within an exhausted envelope.

6. The combination of frame support members positioned parallel with respect to each other, electrode support members positioned parallel to and between said frame members, means for uniting said members to form an electrode unit, electrodes carried 'by said supports, and means for suspending said unit in an exhausted envelope.

7. The combination of frame support members positioned parallel with respect to each other, electrode support members positioned parallel to and between said frame members, means for uniting saidmembers to form an electrode unit, electrodes carried by said supports, and means for susending said unit in an exhausted envelope by means of said electrode support memers.

8. The combination of a plurality of electrode supports, means for binding the same together to form an electrode supporting unit, electrodes carried by said supports, and means for supporting said unit within an exhausted receptacle, and leading-in wires on said support members and extending through said envelope.

In witness whereof, I hereunto subscribe my name this 28th day of August A. D., 9

HENDRIK J. VAN DER BIJL. 

